A major source of dissatisfaction with home security systems is that motion sensors of the systems are often triggered by pets or members of the household. When false alarms occur, they unnecessarily put people in the home in fear. False alarms sometimes also result in monetary fines being charged to the homeowner or renter, as well as loss of credibility of the homeowner or renter with emergency responders. As a result, some people disable the motion sensors of their security system, thus compromising their own security.
Current techniques for preventing false alarms caused by pets or family members have significant limitations. One known technique for preventing false alarms from being triggered by pets or family members relies on aiming the motion sensors of the security system above the height of pets so that they do not sense the pets' motion as they move around the home. This technique can work suitably for dogs, but can easily be defeated by a crawling intruder, and can be triggered by cats and other animals that climb. Another known technique relies on processing the projected sizes of objects on a sensor to determine whether the objects correspond to pets or intruders. This technique does not work well with large animals or when multiple animals are in close proximity to one another. Also, because the projected size of an object on a sensor will vary depending on how close to or how far away the object is from the sensor, the decisions that are made based on the projected size are not always accurate.
Accordingly, a need exists for way to determine when a security system sensor has sensed pets or family members as opposed to intruders so that the security system alarm is not triggered by pets or family members.